20506514665 has 32 divisors (see below), whose sum is σ = 30669972480. Its totient is φ = 12815622144.

The previous prime is 20506514657. The next prime is 20506514669. The reversal of 20506514665 is 56641560502.

It is not a de Polignac number, because 20506514665 - 2³ = 20506514657 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20506514669) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 249304 + ... + 321193.

It is an arithmetic number, because the mean of its divisors is an integer number (958436640).

Almost surely, 2^20506514665 is an apocalyptic number.

It is an amenable number.

20506514665 is a deficient number, since it is larger than the sum of its proper divisors (10163457815).

20506514665 is a wasteful number, since it uses less digits than its factorization.

20506514665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 570601.

The product of its (nonzero) digits is 216000, while the sum is 40.

The spelling of 20506514665 in words is "twenty billion, five hundred six million, five hundred fourteen thousand, six hundred sixty-five".